Conditional

と

V

い-Adj

な-Adj + だ

N + だ

+ と

Means “if”, “whenever”. Used when a result is known or assumed to be true, aka a logical cause-effect relationship. Cannot be used if the result is uncertain. So it cannot be an intention, a request, a desire, an order, etc.

Example

急いそいでないと、遅刻ちこくに着つきます。 If you don’t hurry, you’ll arrive late.

なら

V (casual) + (の)

い-Adj + (の)

な-Adj + (の)

N

+ なら

Means “in the case that/of”. The second part of the sentence is generally an opinion, a request or a suggestion. Adding の adds emphasis. ならば can be used in more formal contexts.

Example

車くるまを使つかうなら、気きを付つけて。 If you’re using a car, be careful.

たら

V (た)

い-Adj い + かった

な-Adj + だった

N + だった

+ ら

Means “if” or “when”. Describes a condition (the first action must be completed before the second action). Used for hypothetical situations and certain results. It is the main word used for conditional.

Example

安やすかったら、買かう。 (If / When) it’s cheap, I’ll buy it.

場合

V (casual)

い-Adj

な-Adj + な

N + の

+ 場合は

場ば合あい means “in the case of”. The second part explains what to do in the situation (instructions, advices, etc). More formal than たら.

Example

地じ震しんの場合は、エレベーターを使わないでください。 In case of an earthquake, please don’t use the elevators.

ば・なければ

Positive form:

V (う → え)

い-Adj + けれ

な-Adj + なら

N + なら

+ ば

Negative form:

V ない

い-Adj ない

な-Adj + で

N + で

+ なければ

See Conjugation Basics for verbs (the う sound transforms the the corresponding え sound).

Means “if”. A conditional relationship without the cause-effect relationship of と. If A happens, then B. Situations must be hypothetical. Generally used for one-time results.

Examples

雨が止めれば、店に行く。 If it stops raining, I’ll go to the store.

おいしいでなければ、食べません。 If it’s not good, I will not eat it.

ばいい

Used for hope about a result. “It would be good if”. Can also be used to give an advice, in a meaning similar to “should”.

Example

宝たからくじが当あたればいいね。 It would be good if I win the lottery…

ばよかった

Used for regret about something that would have been better if done. “It would have been good if”. More emphasis can be added by adding のに.

Example

上着うわぎを持もてばよかった。 I should have brought a jacket.

ば～ほど

V (ば)

+

V (る)

+ ほど

い-Adj い + ければ

+

い-Adj

+ ほど

な-Adj + なら

+

な-Adj + な

+ ほど

Means “the more… the more”. Used by repeating the same verb.

Example

自転車じてんしゃをすればするほど、上手じょうずになります。 The more you bike, the better you get.

Summing up

• と has a logical cause-effect relationship. Certain result.
• なら usually used for opinion, request, suggestion.
• V-たら describes a condition to be met for the result. Usually used for hypothetical situation.
• 場合 explains what to do in a described situation. More formal than V-たら.
• V-ば is a conditional relationship, close to V-たら. Used for hypothetical situations, generally for for one-time results.

とすれば・としたら・とすると

V

い-Adj

な-Adj + だ

N + だ

+ とすれば・としたら・とすると

Means “if we assume that A, B”. としたら is more casual than とすれば. とすると is used for an action that is likely to happen.

Example

電車でんしゃで行くとすると、２０分っぷんかかるです。 If you were to go by train, it would take 20 minutes.

もし(も)

Used with conditional forms ば, と, たら and ても (see Even if ても・でも). もしも puts more emphasis than もし.

Example

もしペットが病気びょうきになったら、動物どうぶつ病院びょういんに行かなきゃ。 If you pet gets sick, you have to bring it to the veterinarian clinic.